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Guy Ottewell

Moon on its way to the eclipse

Insights and a cool chart from astronomer Guy Ottewell. Plus, if you click in, you’ll find photos of waning crescent moons from the past few mornings …

A shadow-band project for August 21

Shadow bands are elusive ripples of alternate light and dark, flitting over the ground or the sides of buildings during a total solar eclipse. How to take part in an International Shadow Band Campaign during the August 21 eclipse.

The eclipse is just 2 lunations away

As we approach another new moon, astronomer Guy Ottewell shares his profound understanding of lunar cycles and the coming total solar eclipse.

The undark nights of summer

Guy Ottewell lives in England. His illustrations of 3-dimensional space are illuminating. Long summer twilights, explained.

Planet circus in May, with explanation

A beautiful spatial view of our solar system from Guy Ottewell, showing the planets’ paths along their orbits in approximately mid-May, 2017, with sightlines to them from the Earth.

Overtaking the king of planets

This is what the opposition of Jupiter means.

Catch Comet Encke this evening!

The comet’s orbital period is short – only 3.3 years – and the orbit is relatively close to Earth. Encke’s Comet is now on its 63rd known visit to our part of space.

Valentine’s Day

Astronomer Guy Ottewell reflects on the planet of love.

Vesta, brightest asteroid, brightest for 2017

If you’ve never spotted an asteroid, now would be a good time to try. Vesta’s 2017 opposition is around now. Guy Ottewell provides charts and explains more.

Thanksgiving evening

There’s the sky we can see, and, beyond that, a whole universe of objects we can’t see with the eye alone. Guy Ottewell gives you a way to project outward on this Thanksgiving evening.